1. Field Of The Invention
This invention relates generally to the art of controlled dispensing and compliance monitoring. It has particular application to the art of unsupervised drug dispensing to a patient although the principles of the invention apply to controllable dispensers of any types of material. The presently preferred embodiment of the invention provides a controlled medication dispenser. The dispenser can be preprogrammed by a drug therapist using a base unit (specially programmed computer) to which the dispenser is temporarily coupled, to permit a patient access to drugs stored in a portable field unit only in accordance with predetermined criteria, such as for example at particular times. A digital display on the dispenser specifies the next dosing time and will instruct the patient on proper make-up doses in the event of missed doses. The portable field unit records actual times of medication dispensing and can easily be debriefed by the base unit (computer) which then prepares a medication compliance report for the drug therapist.
2. Background Of The Invention
"Controlled dispensing" refers to the concept of permitting a user to dispense some item according to a predetermined schedule or set of rules, rather than permitting unrestrained access. A significant application of the art of controlled dispensing relates to drug dispensing.
"Compliance monitoring" refers to the concept of recording a user's actual dispensing activity compared to a previously prescribed regimen. A significant application to the art of compliance monitoring also relates to drug therapy.
As drug research and therapy become more and more sophisticated, drug researchers and therapists have an increasing need to administer complex drug regimens to patients; to restrict access to medications in some instances; and to evaluate the patients' compliance with those drug regimens.
The most accurate way of administering a drug regimen and measuring compliance of a patient or test subject is direct supervision of each dose of medication. The manpower required for this type of drug administration is extraordinary and usually requires hospitalization. The alternative of prescribing a drug regimen and leaving it completely to the patient to follow and report back usually results in poor compliance and inaccurate reports.
Controlled drug dispensers and compliance monitoring equipment provide a middle ground between direct supervision and no supervision so that relatively dangerous drugs can be administered without direct supervision and clinical drug studies can be carried out with relatively high reliability.
As the U.S. Department of Commerce National Technical Information Service Publication PB-278 973 entitled "Possible Designs of Medication Monitors", prepared at the National Jewish Hospital and Research Center, Denver, Colo., for the American Lung Association (April 1978) points out, the genesis of the medication compliance monitor goes back to May 1962. This early concept was for a medication monitor utilizing radioactive material and photographic film to determine when patients removed medication from a medication dispenser.
Since then there have been several publications on different devices utilizing the same principle, as well as field trials. Since the original publication, the interest in the field of patient compliance with drug regimens grew enormously.
"The Unrealized Potential of The Medication Compliance Monitor" was discussed by Thomas S. Moulding, M.D., at the National Jewish Hospital in a February, 1979 commentary appearing in Volume 25, November 2, of Clinical Pharmacology and Therapeutics. That commentary provides some insight to the historical development of the art of medication compliance monitoring. This Moulding commentary discusses an early version of a radiographic-type compliance monitor. As medication compliance monitoring further developed, various arrangements appeared in the literature and marketplace. Moulding describes a radiographic compliance monitor capable of showing dosing patterns. Each container holds a full daily dose of medication. However there is not provided any alerting features to help the patient to remember to take dosages. Processing and interpreting the compliance record are awkward. Potential hazards are associated with the use of a radioactive source. No control mechanisms are used--Access is not controlled nor is the number of dosages taken at one time.
Moulding anticipates the use of strip packaging and microprocessors for improving compliance monitors' design but no practical details are given on how to accomplish these design improvements. It does not appreciate the utility of a device capable of delivering multiple medications in complex regimen. The commentary does not teach how to build a reliable and tamper-proof dispensing mechanism; a successful strategy for field, interface, and base unit electronics and software is not given.
Lederle Laboratories (American Cyanamid Company) developed a digital module for the cap of a medicine bottle for reminding the patient when he last took his medication. This "reminder" cap was intended to help people to take medication at the proper time. However, such an arrangement has certain fundamental inadequacies: The clock does not indicate when the next dosage is due. The patient must still remember the proper dosage schedule. There is no alarm to get the patient's attention when the next dosage is due. The cap has no memory to show the therapist when dosages were taken. There is no control over when the bottle cap is opened or the number of dosages taken after the cap is removed. Also, multiple caps are needed for multiple drug therapies; and the patient is not guided as to how much of each drug is to be taken.
A "Med Tymer" medicine bottle cap was developed by Boston Medical Research, Inc. It includes preprogrammed light and sound alarms that announce when the next dosage is due. 1/day to 4/day schedules are available. However, it also has several functional limitations. Programs are in firmware and are not adjustable. Thus, there is no flexibility of dosing times for a given daily frequency. The cap has a limited lifespan (12 months) and is not reusable or reprogrammable. It is not approved for liquid medications. It has no memory for later reporting of compliance. There is no control over when the cap is opened or the number of dosages taken after the cap is removed. Multiple caps are needed for multiple drug therapies; and the patient is not guided as to how much to take of each medication.
In an article entitled "Medication Monitor for Opthamology" by Yee et al appearing at page 774 of the American Journal of Opthamology, there is described a medication monitor wherein dosing times are recorded in memory for later reporting of compliance. Its functional limits are as follows. There are no alerting features such as an alarm, or clock displays, etc. The electronics provide only a limited memory, i.e. there is no microprocessor to provide alarm and control functions and the limited memory results in limited dosing record resolution. It is only possible to achieve one hour resolution of dosage taken times; and multiple doses within any given hour cannot be recognized. There is no control over when the cap is opened or the number of dosages taken after the cap is removed. Multiple units are needed for multiple drug therapies; and the patient is not guided as to how much to take of each medication.
A sample of the patent literature in this art includes:
U.S. Pat. No. 3,369,697, Glucksman et al, Feb. 20, 1968 PA1 U.S. Pat. No. 3,968,900, Stanbuk, July 13, 1976 PA1 U.S. Pat. No. 4,223,801, Carlson, Sept. 23, 1980 PA1 U.S. Pat. No. 4,293,845, Villa-Real, Oct. 6, 1981